package summer.hot100.v1;

public class Solution309 {
    public int maxProfit(int[] prices) {
        int[][] dp = new int[prices.length][4];
        dp[0][1] = -prices[0];
        for (int i = 1; i < prices.length; i++) {
            dp[i][1] = Math.max(dp[i - 1][1], dp[i - 1][3] - prices[i]);
            dp[i][2] = dp[i - 1][1] + prices[i];
            dp[i][3] = Math.max(dp[i - 1][2], dp[i - 1][3]);
        }
        return Math.max(dp[prices.length - 1][2], dp[prices.length - 1][3]);
    }
}
